JP3362711B2 - Method for manufacturing liquid crystal polymer layer and method for manufacturing display element - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer dispersion type liquid crystal display device in which a liquid crystal and a polymer are dispersed in each other, and to a display device applied to a man-machine interface such as a computer display or a television and a manufacturing method thereof.

[0002]

With the introduction of the Prior Art] computer to the field in recent years social life, the development of man-machine interface has been accelerated. In particular although the field of display is where most developed is urgent, the rely on dark twisted nematic liquid crystal display device having display using two polarizing plates mites have or are at present. Therefore, recently, a polymer dispersed liquid crystal display device has been developed. Since this method does not use a polarizing plate, incident light can be used efficiently. Particularly in the mode in which dichroic dyes are mixed, the appearance when used as a reflection type is remarkable. For example, Fergason is 2
A liquid crystal containing a chromatic dye is encapsulated and dispersed in a polymer (Japanese Patent Publication No. 3-52843, etc., hereinafter referred to as microcapsule type normal PDLC). Doane et al.
A method has been proposed in which a liquid crystal and a polymer are mixed in a colorant-containing dye and a polymer precursor and then polymerized to form a sponge-like phase separation of the liquid crystal and the polymer to prepare a display device (Japanese Patent Laid-Open No. 61-5.
02128, etc., hereinafter referred to as a polymerized normal PDLC).

Further, Hikmet et al. Of Philips Corp. uses a polymer precursor having a liquid crystal state, and forms a polymer in an oriented state by irradiating ultraviolet rays in a state of mixing with the liquid crystal, and the liquid crystal is contained in the gel network. A display element having the structure described above is manufactured (Mol. Cryst. Li
q. Cryst. , 1992, Vol. 213, pp.
117-131, hereinafter referred to as network-oriented PDLC).

[0004]

In this method, unlike the mode shown above, white scattering occurs when an electric field is applied. on the other hand,
We have independently developed a technology to form polymer particles in the state of being oriented (European published patent EPO,
488, 116A2, etc. hereinafter referred to as particle oriented PDLC). However, sufficient brightness and contrast are not obtained in any mode. Also, the drive voltage cannot be said to be sufficiently low.

Therefore, the present invention is to provide a display device in which a liquid crystal and a polymer are aligned and dispersed with each other and which has a good contrast and a low driving voltage, and a manufacturing method thereof.

[0006]

The present invention is a method for producing a liquid crystal polymer layer comprising a liquid crystal and a polymer, which is used in a display device, wherein the polymer is represented by the formula (1) M-U -P-S [in the formula, _{M, CH 2 = CH-, CH 2} = C (CH 3) -
Or an epoxy group, U represents —COO— or —CONR ₁ — when M is CH ₂ ═CH— or CH ₂ ═C (CH ₃ ) —, and M represents In case of epoxy group-
CH ₂ O- to represent, R ₁ represents an H or CH _3, P
Represents an optionally substituted phenylene group, and S represents an organic group. However, when U is -COO-, S
Is a phenylcarbonyl group, p-alkylphenylene
Rubonyl group or p-alkoxyphenylenecarbonyl
If a group, -OCO-CH = CH ₂ or -OCO
-C If (CH ₃₎ a _{= CH 2, -C (CH 3} ) 2 -
(Phenylene which may be substituted) -OCO-CH =
CH ₂ or -C (CH ₃ ) _2- (may be substituted
_{Phenylene) -OCO-C (CH 3)} = is CH ₂ field
If, and - (phenylene) m-OCO-CH = CH 2
Or - (phenylene) m-OCO-C (CH 3) = C
H ₂ (m is 0 or 1) and P is phenyl
Fluorine atom or phenylene group in S
Except when the alkyl group is substituted. ] It is characterized by being formed by polymerizing the polymer precursor containing at least 1 sort (s) of the compound represented by these, without using a copolymerizable photoinitiator. Further, the method for producing a liquid crystal polymer layer of the present invention is characterized in that the polymer precursor comprises a compound of the above formula (1), and in the above formula (1), the group S is M- A U-group is contained, and in the formula (1), the group M is CH ₂ ═CH.
- or _{CH 2 = C (CH 3)} - a and the group U is -COO
−, And in the above formula (1),
The group M is CH ₂ ═CH— or CH ₂ ═C (CH ₃ ) —, the group U is —CONH—, and in the above formula (1), the group M is an epoxy group. Is characterized by. Further, the compound represented by the formula (1) is characterized by having at least two aromatic rings in the compound and an ester group between the aromatic rings, and the compound represented by the formula (1)
The compound represented by the formula (1) has at least two aromatic rings and a urethane group or an amide group between the aromatic rings, and the compound represented by the formula (1) is It is characterized by having at least two aromatic rings and at least one acetylene group between these aromatic rings. Furthermore, in the method for producing a liquid crystal polymer layer of the present invention, the group S of the compound represented by the formula (1) has an aromatic ring to which an alkyl group or an alkoxy group is directly or indirectly bonded. Further, the group S of the compound represented by the above (1) is characterized by having an aromatic ring to which a cyano group, a halogen group or an aromatic ring group is directly or indirectly bonded, and the group represented by the above formula (1) The aromatic ring in the compound represented by is substituted with at least one fluorine atom (provided that in the formula (1), the group M is CH ₂
= CH- or _{CH 2 = C (CH 3)} - and is, the group U -
COO- and the group S is-(phenylene) m-OCO-
CH = CH ₂ or - (phenylene) m-OCO-C
When (CH ₃ ) = CH ₂ (m is 0 or 1)
Excluding cases. ] Further , the group S of the compound represented by the formula (1) contains an optically active group. Further, the present invention is characterized in that in the method for producing a liquid crystal polymer layer, the liquid crystal polymer layer described in any one of the above is sandwiched between a pair of substrates to be formed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to describe the present invention in more detail, it will be described by way of examples with reference to the accompanying drawings.

Example 1 In this example, a polymer precursor is a methacrylic acid ester or an acrylic acid ester derivative, which has two or more aromatic rings in its side chains, and at least one of the aromatic rings is hydrogenated. The polymer precursor having an ester group between the aromatic rings may be used. FIG. 1 shows a cross-sectional view of the horizontal alignment type display device of the present invention. Further, FIG. 2 shows a sectional view of the vertical alignment type display device of the present invention. As described above, the present invention is a technique that can be applied to both the horizontal alignment type and the vertical alignment type. In this embodiment, a horizontal alignment type will be mainly described for simplicity. In all of the examples, a method of manufacturing a device in which, in the case of the vertical alignment type, the device substrate is subjected to vertical alignment treatment and liquid crystal having negative dielectric anisotropy is used will be described. First, the electrodes 2 and 5 were formed on the surfaces of the substrates 1 and 6 having flat surfaces. Either of these electrodes may be a reflective electrode. The surface of these substrates was subjected to orientation treatment. The two substrates were fixed so that the gap between them was 5 μm. This gap does not have to be 5 μm and may be determined according to the application. For example, if it is used as a transmission type, the optical path length is halved, so sufficient contrast cannot be obtained unless it is doubled from 5 microns to 10 microns.

4-Benzyloxyphenyl methacrylate as a precursor of polymer 3

[0010]

[Equation 1]

And liquid crystal 4 (PNOO2: 1-10% of S-1011 as a chiral component, mixed with RODIC, S-428: 1.5% of Mitsui Toatsu Dye Co., Ltd.) as a dichroic dye. When the mixture was encapsulated and the mixture was oriented and irradiated with ultraviolet rays, the liquid crystal and the polymer were phase-separated, and an almost transparent element could be manufactured.

Next is the measurement of the device. A reflection plate was placed on the back surface of the display element, an alternating electric field of 10 kHz was applied between the two electrodes, and the reflectance of light when the voltage was changed was measured. Then, the display state started to reverse at 3.3V (reflectance 5%), and saturated at 4.8V (reflectance 190%). Although slightly smaller than the conventional example, the driving voltage is lowered and the scattering degree is improved. As for the reflectance, the reflectance of white paper is 100%. At this time, it seems that the reflectance is improved by arranging the device so that the orientation direction of the polymer on the device front surface side or the device back surface side is perpendicular to the plane including the incident light direction and the normal to the device surface. In contrast, we used to use
When a device is manufactured by using the photocurable biphenyl derivative 4-biphenylmetallate as a polymer precursor in the same manner as in the present invention, the display state starts to reverse at 3.5V (reflectance 5%). Saturated with OV (reflectance 180%). Here, 100% is the reflectance when a white paper is placed instead of the display element. It can be seen that in this example, the scattering degree is obviously improved at a low voltage.

The characteristics of the device were measured with a transmission type optical system. At this time, the electrodes of the display element substrate are transparent electrodes, and 2
A display element was prepared without adding a chromatic dye, and the brightness of light passing through the element was measured with the brightness of incident light set to 100%. At this time, an aperture was placed immediately before the photodetector in order to remove scattered light from the device. At this time, the diameter of the hole of the aperture was set so that the angle of view of the element was 3 degrees. The electric field applied to the display element was applied under the conditions shown above. At this time, the display state began to reverse at 3.5V (transmission rate 85%), and was saturated at 5.0V (transmission rate 5%). Thus, it can be applied to both the transmissive type and the reflective type.

Next, as an example containing three or more aromatic rings, an example containing an ester group between a biphenyl group and a phenyl group will be shown. For example, 4- (4'-biphenylcarboxy) phenyl methacrylate

[0015]

[Equation 2]

Was used. An element was produced in the same manner as the method shown above and was driven in the same manner. The display state started to reverse at 4V (reflectance 5%) and saturated at 5.5V (reflectance 19
0%). The transmissive type showed the same effect.

Next, an example will be shown in which a polymer precursor containing a naphthalene group and having an ester group added in the opposite direction is used. Devices other than the polymer precursor were manufactured under the conditions shown above. Here, as the UV curable polymer precursor, 4-
(2'-naphthoxycarbonyl) phenyl methacrylate

[0018]

[Equation 3]

Was used. The display state started to reverse at 3V (reflectance 5%), and the display was saturated at 4V (reflectance 80%). The transmissive type showed the same effect.

As described above, the polymer precursor has a skeleton other than those shown above in this example.

[0021]

[Equation 4]

The same effect can be obtained by using the basic skeleton shown in.

Here, the polymerized portion may be any polymerized group used in polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Of course, R in the chemical formula may be an alkyl group or another substituent. Further, a polymer precursor having a polymerized portion that is cured by heat or electron beam can also be used. Regarding the aromatic ring, at least one aromatic ring may be hydrogenated. For example

[0024]

[Equation 5]

Etc. may be used. The aromatic ring is not limited to a phenyl group, and may be a polycyclic aromatic ring such as biphenyl, terphenyl, naphthalene, or anthracene. Although the substitution mode of the aromatic ring is para-substitution, the element can be operated by meta-substitution or ortho-substitution. However, the degree of scattering tends to decrease. Further, here, the aromatic ring does not contain a substituent other than a bond with another aromatic ring, but as described later, a cyano group, a halogen group,
By incorporating a substituent such as an alkyl group or an alkoxy group, excellent characteristics can be exhibited. Further, it is possible to incorporate at least one structure such as a urethane group, an amide group, and an acetylene group, which will be shown later. Further, H in the compound may be replaced with fluorine.

Ultraviolet rays are used here as an external field used at the time of polymerization, and the wavelength and intensity thereof are from 300 nm to 4 nm.
Light having a wavelength of 00 nm and an intensity of 2 mW / square cm was used, but the wavelength and the intensity may be any wavelength intensities as long as the polymer precursor is polymerized. Particularly, when a weak light is irradiated for a long time, when a dichroic dye is used, the dye is less likely to be contained in the polymer, and the characteristics are improved. Further, if a polymerization initiator or a sensitizer is mixed, the polymerization can be effectively advanced. It can also be polymerized with an electron beam. For example, if an electron beam accelerated at 250 KV was used, and the thickness of the substrate on the electron beam incident side was made sufficiently thin (for example, 100 μm) and the electron beam was incident, sufficient polymerization could be achieved. It is also possible to mix a polymerization initiator and polymerize by heat.

The alignment treatment is carried out by a conventionally used means such as rubbing of the substrate, a method of forming an alignment film and rubbing the film, an oblique vapor deposition method, a method using an LB film,
Any method can be used as long as the liquid crystal phase is aligned, such as a method using a vertical alignment agent. In addition, the alignment treatment is effective even with a single-sided substrate. The orientation of the substrate may be in any direction, and the orientation may be different between the front and back substrates, but it is optimized according to the incident direction of the light used and the scattering profile required for the device. There is a need. Further, as will be described later, by tilting the orientation direction of the polymer with respect to the substrate surface, the driving voltage can be reduced and the clear viewing direction can be optimized.

The liquid crystal used here should have a refractive index anisotropy Δn as large as possible. Further, a liquid crystal having a positive dielectric anisotropy can be used. The optimum content of the liquid crystal is 50 to 97% with respect to the polymer monomer. If the liquid crystal content is less than this, it will not respond to the electric field, and if it is more than this, contrast will not be obtained. Further, if a liquid crystal having a high specific resistance is used, it can be driven by an active element.

The dichroic dye used here can be used even if it is not shown here, and the content ratio may be optimized according to the application. Electric field O if dichroic dye is not mixed
A mode in which FF is transparent and white is scattered when the electric field is ON can be set.

Although the chiral component is mixed here, any chiral component may be used, and the content may be determined according to the application. If a large amount is inserted, the drive voltage will be high, but the memory property will appear. Also, it operates as an element without adding a chiral component.

Example 2 In this example, the polymer precursor is a methacrylic acid ester or an acrylic acid ester derivative, and has two or more aromatic rings in the side chains, and at least one of the aromatic rings is hydrogenated. The polymer precursor having a urethane group or an amide group between these aromatic rings may be used. 4-methacryloyloxyphenyl-phenylcarbamate as polymer precursor

[0032]

[Equation 6]

Was used. The manufacturing conditions of the device were as in Example 1.

The electro-optical characteristics of the device were measured by the method of Example 1. The display starts to reverse at 3.5V (reflectance 5
%), Saturated at 5 V (reflectance 180%).

Next, an example in which an amide group is used as the polymer precursor will be shown. Phenylcarbamoylphenyl-4-methacrylate as polymer precursor

[0036]

[Equation 7]

Using the above, an element was manufactured under the same conditions as in Example 1.

The electro-optical characteristics of the device were measured by the method of Example 1. The display starts to reverse at 3.5V (reflectance 5
%), Saturated at 5 V (reflectance 180%).

As described above, the polymer precursor has a skeleton other than those shown above in this example.

[0040]

[Equation 8]

With the basic skeleton shown in, the same effect can be obtained. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Of course, R in the chemical formula may be an alkyl group or another substituent. Further, a polymer precursor having a polymerized portion that is cured by heat or electron beam can also be used. Regarding the aromatic ring, at least one aromatic ring may be hydrogenated. For example

[0042]

[Equation 9]

Etc. may be used. The aromatic ring is not limited to a phenyl group, and may be a polycyclic aromatic ring such as biphenyl, terphenyl, naphthalene, or anthracene. Although the substitution mode of the aromatic ring is para-substitution, the element can be operated by meta-substitution or ortho-substitution. However, the degree of scattering tends to decrease. Further, here, the aromatic ring does not contain a substituent other than a bond with another aromatic ring, but as described later, a cyano group, a halogen group,
By incorporating a substituent such as an alkyl group or an alkoxy group, excellent characteristics can be exhibited. Further, at least one structure such as the ester group shown in Example 1 and the acetylene group shown later can be incorporated. Further, H in the compound may be replaced with fluorine.

Other element constituent elements, manufacturing conditions and applications are the same as in Example 1 (Example 3) In this Example, the polymer precursor is a methacrylic acid ester or an acrylic acid ester derivative,
It has two or more aromatic rings in the side chain, and at least one of the aromatic rings
One may be hydrogenated, and an example having an acetylene group between these aromatic rings is shown. First, an example using a polymer precursor having two polymerized parts is shown. Di (parameter cryloyloxyphenyl) acetylene as polymer precursor

[0045]

[Equation 10]

Example 1 was used for other manufacturing conditions.
Under the same conditions as. The liquid crystal and polymer were phase separated.

The electro-optical characteristics of the display device thus obtained were measured by the same method as in Example 1. The display inversion started at 4 V (reflectance 5%) and was saturated at 6 V (reflectance 210%).

Next, an example using an acetylene compound having one polymerized portion will be shown. Paralyl cryloyloxytran as a polymer precursor with one polymerized part

[0049]

[Equation 11]

Was used. The manufacturing conditions other than the polymer precursor are the same as in Example 1.

The electro-optical characteristics were measured in the same manner as in Example 1,
The display inversion started at 3.5 V (reflectance 5%) and was saturated at 5.5 V (reflectance 200%).

Next, an example using a polymer precursor having two triple bonds and no alkyl side chain is shown. An element was manufactured under the conditions of Example 1. Here, 1- (4′-methacryloyloxyphenyl) -4-phenyl-1,3-butadiyne was used as the polymer precursor.

[0053]

[Equation 12]

Was used.

Next, the electro-optical characteristics of the device were measured by the same method as in Example 1. The display inversion started at 3.5 V (reflectance 5%) and was saturated at 5.5 V (reflectance 200%).

The polymer precursor used here has a general formula as long as it has two polymerization parts.

[0057]

[Equation 13]

For those having one polymerized portion, the general formula

[0059]

[Equation 14]

Can be written as Here, various compounds can be used in combination of X, Y, 1, m, and n. For example, it is possible to connect two acetylene skeletons with n = 2.

When n is a plural number, X is repeated a plurality of times, but of course the skeleton may be changed each time.
The same applies to m. In addition to the aromatic ring and the acetylene skeleton, it may have a skeleton that increases the refractive index anisotropy. Furthermore, these polymer precursors are replaced with other polymer precursors,
For example, it may be used as a mixture with a monofunctional polymer precursor such as biphenyl methacrylate. Here, the polymerized portion is acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid,
Any polymerizable group used for polymers such as vinyl group and epoxy group can be used. Of course, R in the chemical formula may be an alkyl group or another substituent. Further, a polymer precursor having a polymerized portion that is cured by heat or electron beam can also be used. Regarding the aromatic ring, at least one aromatic ring may be hydrogenated. The aromatic ring is not limited to a phenyl group, and may be a polycyclic aromatic ring such as biphenyl, ta-phenyl, naphthalene, and anthracene. Although the substitution mode of the aromatic ring is para-substitution, the element can be operated by meta-substitution or ortho-substitution. However, the degree of scattering tends to decrease. Furthermore, here, the aromatic ring does not contain a substituent other than a bond with another aromatic ring, but as described later, by inserting a substituent such as a cyano group, a halogen group, an alkyl group or an alkoxy group, excellent characteristics can be obtained. Can also be expressed. It is also possible to incorporate at least one structure such as the ester group, amide group and urethane group shown above. Also,
H in the compound may be replaced with fluorine.

In this example, the bifunctional and monofunctional polymer precursors were shown. However, when the bifunctional polymer precursor is mixed with the monofunctional polymer precursor, the driving voltage is low and the heat resistance is high. A display element with good durability can be manufactured.

Example 4 In this example, the polymer precursor is an amide of acrylic acid or methacrylic acid. Biphenylmethacramide as polymer precursor

[0064]

[Equation 15]

Using, the element was manufactured under the same conditions as in Example 3.

The electro-optical characteristics of the device were measured by the method of Example 1. The display starts to reverse at 3.5V (reflectance 5
%), Saturated at 5 V (reflectance 180%).

N-methylbiphenylmethacramide and the like can be used in the same manner.

The polymer precursor used here is

[0069]

[Equation 16]

As shown in the above, it suffices that the side chain opening has an aromatic ring, and even if there are plural aromatic rings, it functions as a display element. In Examples other than this Example, the same can be used as a polymer precursor by changing the ester group connecting the polymerized portion and the side chain portion to an amide group. A display element can be manufactured. The aromatic ring is not limited to a phenyl group, and may be a polycyclic aromatic ring such as biphenyl, ta-phenyl, naphthalene, and anthracene. Although the substitution mode of the aromatic ring is para-substitution, the element can be operated by meta-substitution or ortho-substitution. Here, the aromatic ring does not contain a substituent other than a bond with another aromatic ring, but as will be shown later, a cyano group,
By incorporating a substituent such as a halogen group, an alkyl group or an alkoxy group, excellent characteristics can be exhibited. It is also possible to incorporate at least one structure such as the ester group, amide group, urethane group, and acetylene group shown above. It is also possible to incorporate at least one structure such as the ester group, amide group, urethane, and acetylene group shown above. Further, H in the compound may be replaced with fluorine. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Of course, R in the chemical formula may be an alkyl group or another substituent. Moreover, in this compound, N
Since N is included, H, CH3, an alkyl group and other substituents can be introduced into N. Of course, it may be a polymerizable substituent.

Example 5 In this example, a cyano group, a halogen group, or an aromatic ring is directly or indirectly bonded to the aromatic ring contained in the polymer precursor. As a polymer precursor

[0072]

[Equation 17]

As shown in, a biphenyl methacrylate substituted with a cyano group, a fluoro group, a chloro group, a bromo group, an iodo group, an aromatic ring, etc. was used. The liquid crystal material, substrate relation, manufacturing conditions, and measurement conditions were the same as in Example 1. With respect to the electro-optical characteristics, when the cyano group was substituted, the display state began to reverse at 3V (reflectance 5%) and saturated at 4.5V (reflectance 200%). Substitution of the halogen group improves the reflectance when an electric field is applied, compared to when it is not substituted, and the iodine group (reflectance 195%)
> Bromo group (reflectance 190%)> Chloro group (reflectance 18
5%) 1> Fluoro group (reflectance 180%) in order. When substituted with a phenyl group, the reflectance is 2
Very bright display is possible at 20%.

Although the substitution mode of the aromatic ring is para-substitution, the element can be operated by meta-substitution or ortho-substitution. The basic skeleton of the polymer precursor used here is a phenyl group in the aromatic ring, as well as biphenyl, ta-phenyl, naphthalene,
A polycyclic aromatic ring such as anthracene and a basic skeleton in Examples other than this Example can also be used. For example

[0075]

[Equation 18]

[0076]

[Formula 19]

[0077]

[Equation 20]

[0078]

[Equation 21]

It is sufficient that the substituents shown here are introduced directly or indirectly as shown here, and the number thereof is not limited to one. Also, two or more of the ester groups, amide groups, urethane groups, acetylene groups, etc. shown here, including different types, may be contained. In short, all the compounds shown in the present invention can be used as the basic polymer precursor. Further, the substitution mode is not limited to the bulk substitution, and the meta substitution ortho substitution can be used. Of course, even if a plurality of types of substituents are introduced, the same effect is exhibited. When an aromatic ring is used as a substituent, the aromatic ring may be directly or indirectly substituted by at least one or more or at least one kind of substituents such as those shown here. Further, the polymer precursors shown here or the polymer precursors shown in other examples may be mixed and used. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Of course, R in the chemical formula may be an alkyl group or another substituent. Since the chemical formula 21 contains N, H, CH3, an alkyl group and other substituents can be introduced into N. Of course, it may be a polymerizable substituent.

Example 6 In this example, an example using a polymer precursor containing fluorine is shown. Pentafluorobenzoyloxyphenyl methacrylate as a polymer precursor

[0081]

[Equation 22]

Using, the liquid crystal, the substrate, and the manufacturing conditions are the same as in the first embodiment. When the electro-optical characteristics were measured,
The display state starts to reverse at 3.3V (reflectance 5%), 4.
Saturated at 6 V (reflectance 200%).

The polymer precursor used here is a compound in which fluorine is contained in the polymerized portion other than the above-mentioned examples, for example,

[0084]

[Equation 23]

At least one of Y1, Y2 and Y3 contains fluorine, and it is preferable to use an alkyl group such as H, F, CH3 or CF3, but other substituents may be used. R desirably uses an ester substituent containing at least one or more phenyl groups. For example -CO2-
C6F4-C6F5, -CO2-C6F4-C6F4-
OCO-C6F5 (F may be partially H, or another substituent such as phenyl) may be used. The ester groups may be bonded in reverse. More preferably, the phenyl group is preferably substituted with fluorine. R may be an ether substituent, an alkyl substituent or the like in addition to the ester substituent, but it is basically selected to have a refractive index close to that of liquid crystal. Regarding the fluorine substitution amount and the substitution site, it is preferable to select the fluorine substitution amount and the substitution site such that the polymer precursor is compatible with the liquid crystal before the polymerization and is not compatible with the liquid crystal and the dye after the polymerization. .
R may include the above-described polymerization site, that is, one compound may have a plurality of polymerization sites. For example

[0086]

[Equation 24]

[0087]

[Equation 25]

Compounds such as Further, here, the case where all the substitution modes of the benzene ring are in the rose position is shown, but the meta position or the ortho position may be used. Further, these polymer precursors may be used in admixture with each other or with other polymer precursors such as biphenyl acrylate. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Any substance that can be polymerized by ultraviolet ray or electron beam can be used. In addition to this, a polymerized portion that undergoes thermal polymerization can be used.

Example 7 In this example, an example in which an alkyl group or an alkoxy group is directly or indirectly substituted on an aromatic ring as a polymer precursor will be shown.

First, an example in which the one having an alkoxy group on the aromatic ring is used in Example 1 will be shown. An element was manufactured under the same conditions as in Example 3 except for the polymer precursor. Here, 4- (4'-butoxybenzoyl) was used as the polymer precursor.
Phenyl methacrylate

[0091]

[Equation 26]

Was used. When the electro-optical characteristics were measured by the same method as in Example 1, the display started to reverse at 3V (reversal rate 5%) and was saturated at 4.5V (reflectance 200%).
Similarly, a transmissive type is also effective.

Next, an example in which an aromatic ring having an alkyl side chain is used in Example 1 will be shown. An element was manufactured under the same conditions as in Example 3 except for the polymer precursor. Here, 4- (4'-bentylbenzoyl) is used as the polymer precursor.
Phenyl methacrylate

[0094]

[Equation 27]

Was used. When the electro-optical characteristics were measured by the same method as in Example 1, the display started to invert at 3V (reflectance 5%) and saturated at 4.4V (reflectance 200%).

Next, an example using an example in which an alkyl chain is bonded to the basic skeleton shown in Example 2 will be shown. Here, 4-methacryloyloxyphenyl-4'-butoxyphenyl carbamate was used as the polymer precursor.

[0097]

[Equation 28]

Was used. The manufacturing conditions of the device were as in Example 1. The electro-optical characteristics of the device were measured by the method of Example 1. The display starts to reverse at 3.4V (reflectance 5%),
It was saturated at 4.8 V (reflectance 180%).

Next, an example in which an alkoxy group is bonded to the basic skeleton shown in Example 3 will be shown. An element was produced under the same conditions as in Example 1. Here, 4-methacryloyloxy-4'-hexyloxytran was used as the polymer precursor.

[0100]

[Equation 29]

Was used. The electro-optical characteristics of the device were measured by the same method as in Example 1. Display reversal started at 3.4 V (reflectance 5%) and saturated at 5.4 V (reflectance 200
%).

Next, an example in which an alkyl group or an alkoxy group is indirectly bonded to an aromatic ring is shown.

[0103]

[Equation 30]

Here, the group connecting the aromatic ring and the alkyl group is an ester, ether, amide or alkyl chain. The characteristics do not change much depending on the structure of this place.

Like the polymer precursor used in this example,
By introducing an alkyl group or an alkoxy group, the reflectance can be improved and at the same time the threshold voltage can be lowered. As the basic polymer precursor, the compounds shown in all the examples of the present invention can be used. Regarding the length of the alkyl group or the alkoxy group, experiments were conducted up to 9 carbon atoms, and it was confirmed that the device operates as a device. If the alkyl group or the alkoxy group is too long, the reflectance at the time of transparency is increased and the contrast is deteriorated. Desirably, those having 3 to 6 carbon atoms may be directly bonded to the aromatic ring portion, and ether,
It may be bonded via a hetero atom such as an ester bond. Regarding the substitution position, we did all experiments with para substitution,
The same effect can be expected with meta or para substitution. In some cases, these alkyl groups or alkoxy groups may be substituted with a halogen atom, a cyano molecule or the like having a large dipole moment. Moreover, these substituents may be substituted on a plurality of aromatic rings. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Of course, CH3 of the methacrylic group in the chemical formula may be an alkyl group or another substituent.

Example 8 In this example, the polymer precursor was optically active. The polymer precursor used is 4'-
(2 '' (S) -methylpropoxy) biphenyl-4
-Methacrylate

[0107]

[Equation 31]

The liquid crystal material, the device surroundings, and the manufacturing conditions were as in Example 1. The electro-optical characteristics of the device were measured. Then, the display state starts to reverse at 3V (reflectance 5%),
It was saturated at 4.5 V (reflectance 200%).

Here, the polymer precursors other than those used in this example show the same effect as long as they are optically active. For example, the general formula

[0110]

[Equation 32]

As an example, 4- (2 '(S) -methylpropoxy) phenyl methacrylate

[0112]

[Expression 33]

And the like can be used. That is, a substituent having a chiral center may be introduced into the compounds shown in all the examples of the present invention. Although the substitution mode for the aromatic ring is para substitution here, it may be meta substitution or ortho substitution. At the same time, it may be substituted with another substituent. Also, an optically active polymer precursor can be used as one component of the polymer precursor. Here, the polymerized portion is acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid,
Any polymerizable group used for polymers such as vinyl group and epoxy group can be used. Of course, R in the chemical formula may be an alkyl group or another substituent.

Next, an example in which an optically active one is used as one kind of polymer precursor will be shown. 4 ′-(2 ″ (S) -methylpropoxy) biphenyl-4-methacrylate and 4-
A mixture of 1: 1 biphenyl methacrylate was used as a polymer precursor. Other configurations, manufacturing methods, conditions, etc. are the same as in the first embodiment.

The element thus manufactured had a characteristic intermediate between the characteristic shown in the previous example of this example and the characteristic of the conventional example. The optically active polymer precursor has different molecular swivel ability depending on the skeleton. If the turning ability is too large, the driving voltage will increase, so
As shown here, it is necessary to dilute with an optically inactive polymer precursor.

In this example, the S form was used as the optically active form, but the R form can be used in exactly the same manner. Moreover, although the chiral component was not added to the liquid crystal shown here,
Even if a chiral component is mixed, the contrast and brightness can be further improved.

(Embodiment 9) In this embodiment, an example in which a bifunctional molecule precursor and a monofunctional polymer precursor are mixed is shown. The polymer precursors used here are cyanobiphenyl methacrylate and phenyl dimethacrylate.

[0118]

[Equation 34]

It is a mixed system (here, 2: 1). The mixing ratio is not limited to this. The liquid crystal, elements, and manufacturing conditions were as in Example 1. According to this, the electro-optical properties could be improved in heat resistance and reliability without impairing the properties of the monofunctional polymer precursor (conventionally, the polymer melted at 100 ° C. Insoluble). Similar effects were observed for the polymer precursors in all the examples of the present invention. 1
The bifunctional polymer precursor mixed with the functional polymer precursor is

[0120]

[Equation 35]

In addition, the compound shown in Example 3 and H
used by ikmet et al.

[0122]

[Equation 36]

A polymer precursor having a bisphenol A skeleton having a liquid crystal phase such as

[0124]

[Equation 37]

Compounds such as can also be used. In this case, it is not always necessary to include an aromatic ring. For example

[0126]

[Equation 38]

An acrylic or methacrylic group may be attached to both ends of such an alkyl chain. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, crotonic acid, fumaric acid, maleic acid, vinyl group and epoxy group. Of course , R in the chemical formula may be an alkyl group or another substituent. Also, 2
It may not be functional, and may be, for example, a trifunctional or higher polyfunctional polymer precursor (for example, M7100 (manufactured by Toagosei Co., Ltd.)) (Example 10) In this example, two types of polymer precursors were used. An example is shown. The same substrate as in Example 1 was used. Here, 4-benzoyloxyphenylmethacrylate and methacryloyloxyphenyl-4'-methylphenylcarbamate are used as polymer precursors.

[0128]

[Formula 39]

Using these precursors, 1: 1 (W:
W) was mixed, and a device was prepared under the same conditions as in Example 1.

The electro-optical characteristics of the device were measured by the method of Example 1. The display starts to reverse at 3.5V (reflectance 5
%), Saturated at 5 V (reflectance 180%).

When two or more kinds of polymer precursors can be mixed and used, the precursors to be mixed can be the polymer precursors shown in all the examples of the present invention. Further, the mixing amount and the composition ratio with the liquid crystal are not limited to those in this embodiment, and it is necessary to optimize each time.
Further, as shown in Example 9, a polyfunctional polymer precursor may be mixed in such a mixed system of monofunctional polymer precursors. Here, the polymerized portion may be any polymerized group used for polymers such as acrylic, methacrylic, clontic acid, fumaric acid, maleic acid, vinyl group and epoxy group.

(Embodiment 11) In this embodiment, an example using a substrate subjected to vertical alignment treatment is shown. FIG. 2 shows a sectional view of the display device of this example. A method of forming the element will be described. Example 1 is the same as Example 1 except that the liquid crystal RDP00775 (manufactured by Rodic Co., Ltd., with or without chiral component) is used, in which the substrate surface is subjected to vertical alignment treatment and the liquid crystal has a negative dielectric anisotropy.

The polymer precursor used was 4'-fluorobiphenyl methacrylate.

[0134]

[Formula 40]

It is

The electro-optical characteristics were measured by the method of Example 1. However, an omnidirectional reflector is used as the reflector. Display starts to reverse at 7V (reflectance 100%) 15V
Saturated (reflectance 10%). Since the characteristics are reversed compared to the horizontal orientation type, different applications can be expected. It can be used as a transmission type and can be applied to a light valve. The polymer precursors used here are merely representative of the present invention, and all polymer precursors of the present invention can be used. As the liquid crystal, any of the liquid crystals shown here can be used as long as it has a large dielectric anisotropy of Δn.
Further, it functions as a display element with or without a dichroic dye.

(Embodiment 12) This embodiment shows an example in which the orientation direction of the polymer is tilted with respect to the substrate surface. FIG. 3 shows a cross-sectional view of the display element of this example. A method for manufacturing the element will be described. JAS23 and JIB are used as pretilt alignment treatment agents on the surfaces of substrates 1 and 6 on which electrodes 2 and 5 are formed.
(All manufactured by Japan Synthetic Rubber Co., Ltd.) were mixed and applied at a ratio of 1: 1 and dried, and then subjected to horizontal alignment treatment. A display element was manufactured according to Example 1 using the substrate thus manufactured.

The display starts to reverse at 3V (reflectance 5%) 4
Saturated with V (reflectance 170%).

It can be seen that the driving voltage is low.
The polymer precursors used here are only representative of the polymer precursors of the present invention, and all the polymer precursors of the present invention can be used. Further, this embodiment can be applied to all the embodiments of the present invention.

Example 13 In this example, RDP00 having a high specific resistance is used as a liquid crystal by using the above-mentioned polymer precursor.
536 (made by Rodic), S-1 as a chiral component
011 (manufactured by Merck) S-344 as a dichroic dye
(Mitsui Toatsu Dye Co., Ltd.) is used and an example in which an active element is used for the element substrate is shown.

First, the liquid crystal composition sealed between the substrates will be described. S-1 is added to the liquid crystal RDP00536 shown above.
011 was mixed with 0.5% and S-344 was mixed with 1.5%, and further 4 benzoyloxyphenyl methacrylate 8% and tetrafluorophenyl dimethacrylate 2 used in Example 1 were mixed.
% Mixed.

Next, a substrate with an active element for enclosing the liquid crystal composition will be described. FIG. 4 shows a partial cross-sectional view of the display device of this example. An example in which a MIM element is used as an active element will be shown. As a transparent electrode 2 on the substrate 1, IT
O was formed and the surface was oriented. After the tantalum layer 7 was formed on the substrate 6, the surface thereof was oxidized to form the insulating layer 8 and further the reflective pixel electrode 9 (which is subjected to omnidirectional reflection treatment if necessary) thereon. A protective layer may be provided on the element surface to protect the active element. Furthermore, the surface was subjected to orientation treatment. The substrates 1 and 6 were fixed so that the electrode surfaces face each other with a gap of about 5 μm and the alignment directions of the upper and lower substrates were substantially parallel. Here, the active element substrate side is subjected to the reflection processing to make the counter substrate transparent, but conversely, the opposite substrate side may be subjected to the reflection processing to make the element substrate side transparent. Further, although the reflection layer and the electrode are integrated here, the electrode and the reflection layer may be separated.

The liquid crystal composition described above was sealed in the empty panel thus produced, and the polymer precursor was photopolymerized by irradiation with ultraviolet rays to phase-separate the liquid crystal and the polymer.

When a MIM element driving signal is applied to the display element thus manufactured (selection period 60 microseconds, non-selection period 16 milliseconds), the display is inverted by the signal with a peak value of 35 V and the reflectance is 150%. It was The reflectance is lower than that of the previous embodiment because the aperture ratio of the active element substrate is as low as 70%.

A liquid crystal having a high retention rate, specifically, a high specific resistance (10 10 Ωcm or more), a large dielectric constant, and a large birefringence can be used. it can.

The chiral component is not limited to those shown here and can be used. As the chiral component, those having a chiral center in the polymer precursor as shown in Example 8 can also be used. Also, the mixing ratio is not limited to the amount shown here, but if too much is added, hysteresis tends to become large and the driving voltage tends to increase.

The dichroic dye preferably has a large dichroic ratio with little absorption in the ultraviolet region. The color of the dye can be arbitrarily selected according to the application. The content of the dye is not limited to the amount shown here, but if it is too large, the dye crystallizes or the display becomes dark.

Although the polymerization initiator was not used here, a photosensitizer can also be used. However,
Use with caution because the specific resistance tends to decrease.

As the polymer precursor to be used, the polymer precursors shown in all the examples of the present invention can be used. In particular, when a bifunctional or polyfunctional polymer precursor is mixed, even if the polymer content is reduced, a phenomenon such as image sticking in the display state hardly occurs. The content of the polymer precursor may not be the amount shown here, but if it is too small, the scattering degree becomes weak, and if it is too large, the driving voltage becomes high.

As the polymerization conditions, the conditions shown in Example 1 can be used. However, the resistivity to note the polymerization in prayer ease reduced. Although the light intensity is set to 3 mW / cm ² , it is not limited to this. If the light intensity is weak, the polymerization time is lengthened, and if the light intensity is strong, the polymerization time is shortened. However, if the light intensity is too high, the specific resistance tends to decrease. If it is slightly heated (about 20 to 50 ° C.) during the photopolymerization time, polymerization is easy.

Although aluminum is used here as the reflective electrode to be used, any electrode capable of reflecting light such as silver, nickel, or chromium can be used. Alternatively, the electrodes may be transparent and the reflective background plate 9 may be used on the back side of the device.

Although the MIM element is used here as the active element to be used, any element capable of driving the liquid crystal such as a TFT element can be used as will be described later.

Any method may be used for the alignment treatment as long as it is a treatment for aligning the liquid crystal. As shown in the twelfth embodiment, it is of course possible to incline and orient the substrate surface. Vertical alignment treatment may be performed. However, in this case, a liquid crystal having a negative dielectric anisotropy must be used as the liquid crystal. Further, the orientation treatment direction may be optimized according to the application because the clear viewing direction changes.

In this embodiment, the reflection treatment is not carried out, and it can be used as a transmissive display element or a light valve if no dye is added.

(Embodiment 14) Next, an example in which a color filter is used and combined with an active element will be described. FIG. 5 shows a partial sectional view of a color display element using a TFT element. Practically, the pixels corresponding to each color as shown here are arranged in a mosaic pattern or a grid pattern. For the liquid crystal 4 and the polymer 3 layer, the example 13 can be used as it is. The TFT element section will be described.
First, the gate electrode 11 is provided on the substrate 6, the gate insulating layer 14 is provided thereon, and the semiconductor layer 12 and the drain electrode 1 are provided thereon.
3, the source electrode 10, and the pixel electrode 9 which also serves as the reflection layer (which is subjected to omnidirectional reflection processing as necessary) are formed. A protective layer may be provided on the pixel electrode for protecting the active element. Further, the pixel electrodes were oriented. Next, the counter substrate 1
However, the transparent electrode 2 was formed after the color filter 15 was formed, and the upper surface of the transparent electrode 2 was oriented.

In this way, two substrates were prepared and bonded so that the liquid crystal layer had a thickness of about 5 μm with the electrode side inside. The liquid crystal layer does not have to be 5 μm, but if it is too thick, the driving voltage becomes high and the TFT element cannot drive it. Here, the active element substrate was subjected to reflection processing,
Conversely, the opposite substrate side may be subjected to reflection processing. The position of the color filter may be on the surface side of the display element or on the reflective substrate side. It may be between the electrode and the substrate or between the electrode and the liquid crystal layer.

A liquid crystal and a polymer precursor mixture according to the display mode were sealed in this gap, and an external field was applied if necessary to manufacture a device.

As for the liquid crystal, polymer precursor, dichroic dye, chiral component and manufacturing conditions used here, Example 13 can be used.

In this embodiment, the reflection treatment is not carried out, and it can be used as a transmissive display element or a light valve if no dye is added.

An example in which the active element is used has been shown above, but the present embodiment makes it possible to manufacture a reflective large-capacity color display element and further enable full-color display.

In this embodiment, a TFT is used as an active element.
In addition to the elements and MIM elements, T different from the configuration shown here
FT and MIM elements can also be used, and active elements using a ferroelectric can be used in exactly the same manner.

Example 15 In this example, an example in which a polymerizable compound having an epoxy group is used as at least one component as a polymer precursor will be shown. here,

[0163]

[Formula 41]

A display element was manufactured in accordance with Example 1 using the above, and other materials and manufacturing methods. However, as a photopolymerization initiator, SP-150 manufactured by Asahi Denka Co., Ltd. was used in an amount of 5% based on the polymer precursor. The display element thus manufactured exhibits the same element characteristics as those of the case where the methacrylic or acrylic polymer shown in the previous example is used.
The display state began to reverse at V, and the display state reversed at 5V.

The high molecular weight precursor used in this example is a compound in which the polymerized portion has an epoxy group in the previous example, and is mainly

[0166]

[Equation 42]

[0167]

[Equation 43]

[0168]

[Equation 44]

[0169]

[Equation 45]

[0170]

[Equation 46]

[0171]

[Equation 47]

[0172]

[Equation 48]

[0173]

[Equation 49]

It is a compound represented by: Z in the chemical formula is 0 or N, and in the case of N, one more epoxy group or side chain can be introduced. Here, a compound derived from epichlorohydrin, which is the most general epoxy group, is shown, but it goes without saying that any substituent may be introduced as long as the epoxy group is introduced. Further, alkyl, ether, ester, amide, urethane or the like can be used as a spacer between the epoxy group and the aromatic ring. The electro-optical characteristics of the display element using each of the compounds shown here show a tendency similar to the result in the above-mentioned examples, but the driving voltage tends to increase as a whole.

Regarding the photopolymerization initiator, in addition to SP-150, S
P-170, UV-1014, UVE-10 manufactured by GE
16, UCC's Cyracure UVI-697
4, UVI-6990, etc. can be used as long as they act as an initiator, a sensitizer or a polymerization catalyst when the epoxy resin is cured by light. Further, the mixing ratio may be a catalytic amount mixed with the polymer precursor, and the absolute amount may be optimized each time because it varies depending on the polymer premedium to be used. However, if the mixing ratio is too large, the specific resistance of the device decreases, and the reliability also decreases.

(Example 16) In this example, the polymer precursor prepared in the previous example was previously polymerized, heated to be compatible with the liquid crystal, and cooled to remove the polymer from the liquid crystal. An example of precipitation will be shown.

The polymer precursor used was 4-menthyloxyphenylmethacrylate used in Example 1, the liquid crystal was TL202 manufactured by Merck, the chiral component was CB15 manufactured by BDH, and the dichroic dye was Mitsui Higashi. Pressure dye S-
428 were mixed. First, the polymer precursor was polymerized by UV polymerization. This was heated at 120 ° C. to make it compatible with the liquid crystal and sealed between two substrates with an alignment-treated electrode. This panel was cooled at 1 ° C./min to deposit a polymer in an oriented state. The slower the cooling rate, the better, and if cooled too rapidly, the polymer will precipitate without orientation.

In this embodiment, if the ratio of polymer to liquid crystal is between 3:97 and 50:50, it functions as an element. Further, it is not necessary to add a chiral component or a dye. The polymer precursor, the liquid crystal, the chiral component, and the dichroic dye may be materials other than those shown here as long as they are the materials shown in the previous examples. Although two substrates are used here, it is also possible to apply them on one substrate and perform the same treatment, and further form a counter electrode to form a display element. Further, the liquid crystal polymer layer formed on such a single substrate may be attached to face each other to form an element. In addition, an active element can be used as the above-mentioned substrate, whereby a large capacity display element can be produced. Further, it is possible to form a display in color by combining it with a color filter as shown in the previous embodiment.

Example 17 In this example, the polymer precursor prepared in the previous example was preliminarily polymerized, heated to be compatible with the liquid crystal, and then cooled to remove the polymer from the liquid crystal. An example of precipitation will be shown.

The polymer precursor used was 4- (p-bentylbenzoyloxy) phenyl methacrylate, the liquid crystal was MJ90657 manufactured by Merck, the chiral component was CM20 manufactured by Chisso, and the dye was manufactured by Mitsui Toatsu Dye. S-3
44 were mixed. First, UV polymerization of the polymer precursor,
Polymerized. This and liquid crystals were made compatible with each other by using methyl ethyl ketone as a solvent, and spread on a substrate with electrodes subjected to an alignment treatment. This panel was heated and dried at 50 ° C., the solvent was distilled off, and the polymer was deposited in an oriented state. After that, a counter electrode or a substrate with a counter electrode was attached to form a display element.

If the polymer is in a poorly oriented state, the solvent may be distilled off and then the heat-cooling treatment as shown in Example 16 may be carried out.

In this embodiment, if the ratio of the polymer to the liquid crystal is between 3:97 and 50:50, it functions as an element. Moreover, it is not necessary to add a chiral component or a dye. Polymer precursors, liquid crystals, chiral components, dichroic dyes, and solvents other than those shown here can be used as long as they are the materials shown in the previous examples. Although two substrates are used here, it is also possible to apply them on one substrate and perform the same treatment, and further form a counter electrode to form a display element. Further, the liquid crystal polymer layer formed on such a single substrate may be attached to face each other to form an element. In addition, an active element can be used as the above-mentioned substrate, whereby a large capacity display element can be produced. Further, a color display can be prepared by combining with a color filter as shown in the previous embodiment.

(Embodiment 18) In this embodiment, among the substrates for orienting the liquid crystal and the polymer, at least the incident light side substrate orientation processing direction 16 is the main light incident direction 18 and the substrate normal direction 19. Here is an example orthogonal to the plane containing. A simple layout is shown in FIG. In the present embodiment, the orientation processing direction 16 of the substrate on the back side is the same as the front side, and as a comparative example, an example is shown in which the orientation processing method is rotated 90 degrees with respect to the present embodiment and the display elements are arranged. As for the structure and manufacturing method of the used display element, all of the examples shown in the present invention can be used. FIG. 7 shows the electro-optical characteristics of the display device in which the reflection plate 20 is arranged by using the system in which the dichroic dye and the chiral component are mixed. The solid line shows the present embodiment, and the broken line shows the comparative example. Thus, in electro-optical characteristics, the reflectance could be improved by about 30%. Regarding the orientation treatment direction on the substrate on the back side, the same effect as shown in this embodiment can be obtained in any direction other than the same direction as the front side.

(Embodiment 19) In this embodiment, the wavelength correction plate 2 is provided on the back side of the substrate sandwiching the layer in which the liquid crystal and the polymer are oriented and dispersed.
An example in which 1 and a reflection plate or a light scattering plate 20 are arranged is shown.

FIG. 8 shows an example in which the liquid crystal and polymer are horizontally aligned with respect to the substrate surface, and FIG. 9 shows an example in which the liquid crystal and polymer are vertically aligned with respect to the substrate surface. Here, the principle will be described using a system in which a dichroic dye is mixed with liquid crystal and a chiral component is not added, and a 1/4 wavelength plate is used as a wavelength correction plate.

First, referring to FIG. 8, the incident light can be considered by decomposing it into vertically and horizontally polarized light as shown in the figure. At this time, the liquid crystal / polymer layer 17 is assumed to be aligned in the horizontal direction 16. Further, the quarter-wave plate 21 is arranged at an angle of about 45 degrees with the alignment direction 16 of the liquid crystal / polymer layer.

When no electric field is applied, the vertically polarized light is transmitted through the liquid crystal / polymer layer 17 without being absorbed by the dye and is transmitted through the quarter wavelength plate 21 to be reflected or scattered, and is again returned to 1/4.
When passing through the wave plate, the plane of polarization is rotated by 90 degrees. Therefore, absorption occurs due to the dye in the liquid crystal / polymer layer,
No reflected light appears on the surface. On the other hand, horizontally polarized light is absorbed by the dichroic dye in the liquid crystal / polymer layer.

Next, when an electric field is applied, absorption by the dichroic dye is reduced. At this time, when vertical polarized light is incident, it passes through the liquid crystal / polymer layer and further passes through the quarter wavelength plate to be reflected or scattered. When passing through the quarter wavelength plate again, the plane of polarization is rotated by 90 degrees. There is. Therefore, light is then scattered by the liquid crystal / polymer layer. Next, when horizontal polarized light enters, light scattering occurs in the liquid crystal / polymer layer. According to this, all polarized light, that is, natural light can be efficiently modulated by this display element.

Next, FIG. 9 will be described. Here, the liquid crystal / polymer layer 17 is oriented (16) vertically with a slight inclination in the horizontal direction 23 with respect to the substrate surface. The quarter-wave plate 21 is arranged at an angle of about 45 degrees with respect to the horizontal direction.

When no electric field is applied, neither the vertically polarized light nor the horizontally polarized light is scattered or reflected, and is returned.

When an electric field is applied, the liquid crystal and dichroic dye
Mainly oriented in the horizontal direction 23. When vertically polarized light is incident on this, the light is transmitted through the liquid crystal / polymer layer, transmitted through the quarter-wave plate, scattered or reflected, and transmitted again through the quarter-wave plate. At this time the polarization plane is rotated 90 degrees, and the absorption by the dye in the liquid crystal / polymer layer, will be subject to scattering at the liquid crystal / polymer interface at the same time. Next, when horizontally polarized light is incident, the dichroic dye in the liquid crystal / polymer is absorbed and at the same time, the scattering at the liquid crystal / polymer interface is also received. In this way, all polarized light, that is, natural light can be effectively modulated.

The above construction can be applied to all the embodiments of the present invention. For example, it can be applied even when a chiral component is mixed, and can be similarly applied to a system in which no dichroic dye is mixed, and the scattering intensity can be improved. Of course, large capacity display can be performed by combining with an active element, and color display can be performed by combining with a color filter.

(Embodiment 20) This embodiment shows an example in which two sets of the display elements shown in the previous embodiment are combined. FIG. 10 shows the configuration of this embodiment. Here, two sets of horizontally oriented display elements are combined with their orientation directions orthogonal to each other. Regarding the operation principle, it can be considered that the same operation is performed by disposing another set of display elements in the nineteenth embodiment instead of the wavelength correction plate and the reflection plate so that the alignment directions are orthogonal to each other. Display element i.e. contain no chiral component, or slightly had the present invention, in order to have a polarization dependence in the scattering property at the time of electric field application, it has been transmitted without being Oite scattered first to the first sheet of the display device By scattering the polarized light with the second display element arranged so as to scatter the polarized light, all polarized light, that is, natural light can be efficiently modulated.

The above configuration can be applied to all the embodiments of the present invention. For example, it can be applied even when a chiral component is mixed, and can be similarly applied to a system in which no dichroic dye is mixed, and the scattering intensity can be improved. Of course, large capacity display can be performed by combining with an active element, and color display can be performed by combining with a color filter.

The compounds shown in all the above examples can be used as a mixture with the compounds in the other examples.
In that case, the electro-optical characteristics are often intermediate between the characteristics when each compound is used.

In all of the above-mentioned embodiments, the display can be easily viewed by providing a non-reflection layer or a reflection diffusion layer on the surface of the display element.

In all of the above examples, the display element in which the chiral component is not mixed or slightly mixed has polarization characteristics and therefore can be used as an electric field control type polarization element.

[0198] The above mentioned display device according to the present invention, as is, it is possible to easily see remarkably brighten the reflection type display device conventionally dark saw Zuraka', also enables combined with traditional was difficult active element It became possible to manufacture a large-capacity reflective display. Furthermore, colorization is possible. This enables a reflective full-color large-capacity display of a computer terminal and a reflective wall-mounted TV. Also, in a simple direction,
It can be used as an electric field control type polarization element.

[Brief description of drawings]

FIG. 1 is a diagram simply showing a cross section of a horizontal alignment display element according to Example 1 of the present invention.

FIG. 2 is a diagram simply showing a cross section of a vertical alignment type display element in Example 1 of the present invention.

FIG. 3 is a diagram simply showing a cross section of a tilted alignment type display element according to Example 12 of the present invention.

FIG. 4 is a diagram simply showing a partial cross section of a display element with active elements according to Example 13 of the present invention.

FIG. 5 is a diagram simply showing a partial cross section of a display element with a color filter according to Example 14 of the present invention.

FIG. 6 is a diagram simply showing a cross section of a display element according to Example 18 of the present invention.

FIG. 7 is a diagram showing electro-optical characteristics of a display element according to Example 18 of the present invention.

FIG. 8 is a diagram simply showing a cross section of a horizontal alignment display element according to Example 19 of the present invention. (A) shows a diagram when no electric field is applied, and (B) shows a diagram when an electric field is applied.

FIG. 9 is a diagram simply showing a cross section of a vertical alignment display element according to Example 19 of the present invention. (A) shows a diagram when no electric field is applied, and (B) shows a diagram with no electric field.

FIG. 10 is a diagram showing a double-layered display element according to Example 20 of the present invention. (A) is a diagram when no electric field is applied,
(B) shows a diagram when an electric field is applied.

Continuation of the front page (31) Priority claim number Japanese Patent Application No. 4-9540 (32) Priority date January 22, 1992 (January 22, 1992) (33) Country of priority claim Japan (JP) (31) Priority claim number Japanese Patent Application No. 4-106899 (32) Priority date April 24, 1992 (April 24, 1992) (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 4-140343 (32) Priority date June 1, 1992 (June 1, 1992) (33) Priority claiming country Japan (JP) (56) Reference JP-A-5-230122 (JP, A) Kaihei 5-224187 (JP, A) JP 5-105878 (JP, A) JP 3-209424 (JP, A) JP 2-116824 (JP, A) JP 63-170485 ( JP, A) JP 5-119304 (JP, A) JP 4-293996 (JP, A) JP 4-296719 (JP, A) JP 4-274219 (JP, A) JP flat 4-227684 (JP, a) (58 ) investigated the field (Int.Cl. ^7, DB name) C09K 19/00 - 19/56 G02F 1/1334 CA (STN) R GISTRY (STN)

Claims (14)

(57) [Claims] 1. A method for producing a liquid crystal polymer layer for use in a display device, which comprises a liquid crystal and a polymer, wherein the polymer is represented by the formula (1) M-UPS. M _{is, CH 2 = CH-, CH 2} = C (CH 3) -
Or an epoxy group, U represents —COO— or —CONR ₁ — when M is CH ₂ ═CH— or CH ₂ ═C (CH ₃ ) —, and M represents In case of epoxy group-
CH ₂ O- to represent, R ₁ represents an H or CH _3, P
Represents an optionally substituted phenylene group, and S represents an organic group. However, when U is -COO-, S
Is a phenylcarbonyl group, p-alkylphenylene
Rubonyl group or p-alkoxyphenylenecarbonyl
If a group, -OCO-CH = CH ₂ or -OCO
-C If (CH ₃₎ a _{= CH 2, -C (CH 3} ) 2 -
(Phenylene which may be substituted) -OCO-CH =
CH ₂ or -C (CH ₃ ) _2- (may be substituted
_{Phenylene) -OCO-C (CH 3)} = is CH ₂ field
If, and - (phenylene) m-OCO-CH = CH 2
Or - (phenylene) m-OCO-C (CH 3) = C
H ₂ (m is 0 or 1) and P is phenyl
Fluorine atom or phenylene group in S
Except when the alkyl group is substituted. ] The manufacturing method of the liquid crystal polymer layer characterized by forming by polymerizing the polymer precursor containing at least 1 sort (s) of compound represented by this, without using a copolymerizable photoinitiator. 2. The method for producing a liquid crystal polymer layer according to claim 1, wherein the polymer precursor comprises a compound of the above formula (1). 3. In the above formula (1), the group S is M—U.
The method for producing a liquid crystal polymer layer according to claim 1, further comprising a group. 4. In the formula (1), the group M is CH ₂ ═
CH- or _{CH 2 = C (CH 3)} - a and the group U is -C
It is OO-, The manufacturing method of the liquid crystal polymer layer of Claim 1 characterized by the above-mentioned. 5. In the formula (1), the group M is CH ₂ ═
CH- or _{CH 2 = C (CH 3)} - a and the group U is -C
The method for producing a liquid crystal polymer layer according to claim 1, wherein the method is ONH-. 6. The method for producing a liquid crystal polymer layer according to claim 1, wherein the group M in the formula (1) is an epoxy group. 7. The liquid crystal polymer layer according to claim 1, wherein the compound represented by the formula (1) has at least two aromatic rings in the compound and an ester group between the aromatic rings. Manufacturing method. 8. The liquid crystal according to claim 1, wherein the compound represented by the formula (1) has at least two aromatic rings in the compound and a urethane group or an amide group between the aromatic rings. Method for producing polymer layer. 9. The liquid crystal according to claim 1, wherein the compound represented by the formula (1) has at least two aromatic rings in the compound and at least one acetylene group between the aromatic rings. Method for producing polymer layer. 10. A group S of the compound represented by the formula (1).
The method for producing a liquid crystal polymer layer according to claim 1, wherein has an aromatic ring to which an alkyl group or an alkoxy group is directly or indirectly bonded. 11. A group S of the compound represented by the formula (1).
Is a cyano group, a halogen group, or an aromatic ring group having an aromatic ring directly or indirectly bonded to the liquid crystal polymer layer according to claim 1. 12. The compound in the compound represented by the formula (1)
The incense ring is substituted by at least one fluorine atom
Ru[However, in the formula (1), the group M is CH. ₂ = CH- or C
H ₂ = C (CH ₃ )-, The group U is -COO-,
The group S is-(phenylene) m-OCO-CH = CH ₂ Also
Is-(phenylene) m-OCO-C (CH ₃ ) = CH
₂ The case where (m is 0 or 1) is excluded. ]This
The method for producing a liquid crystal polymer layer according to claim 1, wherein
Law. 13. A group S of the compound represented by the formula (1).
The method for producing a liquid crystal polymer layer according to claim 1, wherein is an optically active group. 14. A method for producing a liquid crystal polymer layer, comprising forming the liquid crystal polymer layer according to claim 1 by sandwiching it between a pair of substrates.